Control of a LV Microgrid with Peer-to-PeerEnergy Trading

1. Control of a LV Microgrid with
Peer-to-Peer
Energy Trading
Presenter:
V.D.V.Sriram

2. Introduction
 P2P energy trading refers to direct energy trading among prosumers
and consumers.
 A P2P system architecture was developed. A P2P energy trading
platform, Elecbay, was designed.
 Peer-to-Peer (P2P) energy trading represents direct energy trading
between peers, where energy from small-scale Distributed Energy
Resources (DERs) in dwellings, offices, factories, etc, is traded among
local energy prosumers and consumers.
 A P2P energy trading platform was designed and P2P energy trading
was simulated using game theory.
 Test results in a LV grid-connected Microgrid show that P2P energy
trading is able to improve the local balance of energy generation and
consumption.
 Moreover, the increased diversity of generation and load profiles of
peers is able to further facilitate the balance.

3. Micro Grid
A microgrid is a decentralized group of
electricity sources and loads that normally
operates connected to and synchronous with
the traditional wide area synchronous grid
(macrogrid), but can also disconnect to "island
mode" and function autonomously as physical or
economic conditions dictate.
Microgrids are best served by local energy
sources where power transmission and
distribution from a major centralized energy
source is too far and costly to execute.
In this case the microgrid is also called an
autonomous, stand-alone or isolated microgrid.

4. In this way, microgrids improve the
security of supply within the microgrid cell, and
can supply emergency power, changing
between island and connected modes. They
also offer an option for rural electrification in
remote areas and on smaller geographical
islands. As a controllable entity, a microgrid can
effectively integrate various sources of
distributed generation (DG), especially
renewable energy sources (RES).

5. Control of a LV Microgrid with Peer-to-Peer
Energy Trading
• The control of the local distribution network with P2P energy trading in the control layer before and
during the exchanging time period.
• Case studies are carried out in order to demonstrate the impact of P2P energy trading on the voltage
control system of a grid-connected LV Microgrid. Simulation results show that the proposed voltage
control system is sufficient for supporting the P2P energy trading in the Microgrid based on “Elecbay”.
The total number of operation times of the OLTC is reduced with P2P energy trading compared to the
reference scenario.
• In a LV Microgrid, voltage is sensitive to active power. With the integration of P2P energy trading, the
changes of active power generation and consumption in the Microgrid become even more frequently.
• There are a number of actions that the DSOs are able to take before and during each Settlement
Period. These control methods are categorised into two separate control systems and introduced in
this chapter.

6. Control of a grid-connected LV Microgrid with P2P energy
trading :
According to the P2P energy
trading platform “Elecbay” is used
for each Settlement Period, the
control systems are designed to be
operated between the gate
closure and the end of that
Settlement Period by the DSOs.
There are two separate control
systems which are necessary for
“Elecbay”. They are demonstrated
in Fig. 3.1.

7. Voltage control of a grid-
connected LV Microgrid
with P2P energy trading
• There are two types of voltage control for a grid
connected LV Micro grid with P2P energy
trading:
1. Droop control,
2. On-Load-Tap-Changer control.
• Droop control of DGs and OLTC control are used
in the proposed voltage control system
introduced in this topic, and are developed as
illustrated in the following sub-sections.

8. Droop control
Voltage / reactive power droop
control of DGs is designed and
simulated as follows.
Determining the droop
Voltage / reactive power droop
control is used for reducing the
voltage excursions . A typical
droop characteristic of a DG is
shown in Figure below.
The droop characteristic is described by:
(4.1)

9. On-Load-Tap-
Changer control
• Transformers can regulate the voltage at all voltage levels.
With an OLTC transformer, by triggering proper tap
actions, reactive power produced by all DGs is able to be
reduced. Therefore, the conditions for triggering a tap
change action need to be addressed.
• The OLTC control is developed in two steps:
1. Determining the monitoring bus;
2. Defining the conditions for triggering tap actions

10. Conclusion Two necessary control systems for implementing the P2P
energy trading platform “Elecbay” in the distribution
networks were proposed the bid acceptance/rejection
system and the voltage control system.
The former was designed to operate after the gate closure
and before the start of energy exchange, while the latter
was designed to operate during the energy exchanging
time period.
The voltage control system was further developed in
details. Droop control and OLTC control were used in the
voltage control system. For droop control, the method of
determining the droop for DGs was illustrated.
The simulation by iterating power flow calculation was
explained. For OLTC control, the method of determining
the monitoring bus was demonstrated.

11. THANK YOU